Heavy duty earthworking machines for ripping are provided with ripper means that includes a shank adjustably mounted on a pivoted arm which is hydraulically moved in and out of the ground, a replaceable ripper tip, and in some cases a replaceable guard which is commonly referred to as a shin protector which covers portions of the shank adjacent to the tip which would otherwise tend to wear away during ripping operations. The ripper tip and shin protector can be replaced when necessary, while the shank ordinarily has a useful life about as long as the machine if it is protected by a shin guard.
Ripper shanks commonly have a very heavy upper portion with a tapered end portion that extends diagonally downwardly from the upper part of the shank. Most tapered end portions of ripper shanks are generally wedge-shaped and fit into a complementary socket in the replaceable ripper tip. Such shank end portions are weaker than the upper shank and are frequently further weakened by a transverse bore for receiving a mounting pin for the removable ripper tip.
One U.S. patent discloses a means for transferring ripping forces from the tip to a higher location on the shank which is stronger; but even this does not entirely protect the relatively weak lower end portion of the ripper shank. In addition, the structure illustrated in the patent utilizes the conventional wedge-shaped ripper shank extremity which seats in a complementary socket in the replaceable ripper tip; and such parts are relatively difficult and expensive to manufacture due to the shape of the shank extremity and the need for a good fit between it and the ripper tooth socket.
Another U.S. patent discloses a device in which a replaceable ripper tip has a frusto-cylindrical mounting stub which seats in a socket, and the replaceable tip is held in place by a long bolt which extends through a bore in the lower end portion of the shank and screws into a threaded blind bore in the rear of the mounting stub. Yet another U.S. patent discloses another type of wedging mounting for a replaceable scarifying tooth, but that mounting presents the same manufacturing problems heretofore noted.